(The DOCTOR walks into the transfer section. He checks the operating panel and hearing a noise steps back. VARAN grabs him round the neck.)

VARAN: Die, overlord, die!

(Two armed guards run into the transfer section. They see that VARAN has managed to pull the DOCTOR into an Overlord transfer cubicle and that they are
struggling behind the glass with the Solonians arms still around the DOCTOR'S neck. The cubicle flares to blue as they transmat...)

2: INT. SOLOS. TRANSFER STATION (NIGHT)

(...down to the surface of Solos. As they tumble out of the cubicle, the DOCTOR delivers an elbow-jab to VARAN and struggles free. He then hits him with the
Time Lord's container and manages a forearm jab with his free arm, knocking the Solonian to the ground. VARAN unsheathes his sword and raises his arm but the
DOCTOR puts a two-fingered nerve hold on VARAN'S throat, paralysing the warrior.)

DOCTOR:(Angrily.) Now you listen to me, Varan! For the last time, I tell you I am not an Overlord! I've come to help your people but I must
find Ky.VARAN: Ky is my enemy! I will destroy him and you too, Overlor...!

(The DOCTOR increases the pressure of the hold, chocking off VARAN'S words.)

DOCTOR: You will take me to Ky or I will leave you here for the guards to find. Now, do you give me your word as a warrior?

(VARAN manages a nod and the DOCTOR releases the hold.)

DOCTOR: Lead the way.

(VARAN leads the DOCTOR down the passage to the airlock. As they proceed, they suddenly hear a series of whooshing sounds from overhead and multi-coloured
glows penetrate the corridor from the outside.)

DOCTOR: What the blazes is that?VARAN: Firestorms.DOCTOR: Firestorms, is that all?VARAN: It is the wrath of the gods.DOCTOR: It's a simple atmospheric disturbance, Varan, and something very much to our advantage.

(They come to the counter. VARAN checks in and then looks at the DOCTOR.)

DOCTOR: Well, now what's the matter?VARAN: You have no mask. When the sun rises, you will not be able to breathe the air on Solos.

(The DOCTOR calmly opens the inner door using the palm-print sensor.)

VARAN: No Earthman can.DOCTOR: Did I say I was an Earthman?

(VARAN looks at him in suspicion. The DOCTOR steps through into the airlock.)

3: INT. SOLOS. TRANSFER STATION. AIRLOCK (NIGHT)

(VARAN follows and operates the controls on the outer door. They step out into the night.)

4: EXT. SOLOS. CAVE MOUTH (NIGHT)

(Sat next to their fire, JO and KY watch the display of firestorms from the cave mouth. Glows of red and green light up the blackness of the night and sparks
bounce along the ground. The constant screeching of the storm echoes into the cave. KY is calm at the sight but JO flinches from the display.)

JO: How long do they usually last?KY: The firestorms? First it was a few minutes, now it can go on all night. Each one longer than the last, terrifying my people.

(A particularly close screech makes JO jump.)

JO: Surely they're used to these thunderstorms?KY: There were no firestorms on Solos - until the Marshal began his experiments.JO: Experiments?KY: To make our air breathable for the Overlords but not for the Solonians.

(Another close explosion lights up the interior of the cave with a red glow.)

KY: It would mean the end of my people, Miss Grant.

(A fierce white glow fills up the entrance. JO watches as it illuminates a fully formed mutant. The creature is upright with rounded-claw hands and feet. Its
thorax narrows down from a humped, ridged back to a narrow waist and it has an elongated abdomen which curls down almost to the ground like a huge tail. The
mutant roars with fright from the firestorm. JO is equally as frightened and screams, clutching onto KY.)

JO: There - look!KY: It's alright. They're harmless.JO: But it's horrible!KY: They're people - my people. Or at least they were before the Marshal's experiments.

(The mutant stumbles closer towards them. Its skin can be seen to be layered like that of an armadillo and two mandibles curve down from its face. KY picks
up a branch from the fire and approaches the mutant, waving the torch.)

KY: Back!

(The mutant turns and starts to stumble away, showing its two large unblinking eyes in the light. KY returns to JO.)

JO: I thought you said they were harmless.KY: I don't understand it. Perhaps it's the firestorm, usually they're alright. It'll be safer further back in the cave.

(They move down into the darkness, KY carrying his improvised torch for illumination.)

5: INT. SOLOS. CAVE (NIGHT)

(KY leads the way into a large cavern, whose walls glow with a red and green light. All seems still, but suddenly several mutants come stumbling and roaring
out of the darkness. KY seems that there are too many of them. He looks round and points to a small side passage.)

KY: We'd better hide in here.

(JO and KY retreat down the passage. It ends with a smaller nook which KY guides JO into.)

KY: Don't worry! ___.

(He turns back to face the mutants with his torch.)

JO: Be careful, Ky.

(JO watches nervously as KY starts to jab at the mutants with the flaming torch.)

6: SPACE

(Up above the surface of the planet, the firestorms erupt against the hull of Skybase in a shower of flaring explosions...)

7: INT. SKYBASE ONE. LABORATORY

(The noise of the storms penetrates the hull. The MARSHAL is in the laboratory, looking down contemptuously at a blackened and sulking JAEGER who sits on the
floor.)

MARSHAL:(Mocking.) Professor Jaeger, one of the Empire's greatest scientific minds foiled by a simple booby trap.JAEGER: The Doctor said it was an experiment.MARSHAL: A booby trap, Jaeger, so he could escape.JAEGER: It was a particle reversal - I know it was.MARSHAL:(Snaps.) Forget particle reversal - get those rockets ready! You'll have to go ahead on your own now.

(JAEGER climbs to his feet.)

JAEGER: Marshal, you don't realize? I'm just not ready. Without particle reversal, the whole process is too dangerous. It could get completely out of
hand.MARSHAL: Jaeger, will you get this into your maundering egghead? I want the atmosphere on the planet changed and I want it changed now! Clear?

(He opens his baton radio.)

MARSHAL: Get me Stubbs and Cotton. I want to see them right away. I'll be in my office.

(He snaps the radio shut.)

8: INT. SKYBASE ONE. CORRIDOR OUTSIDE THE MARSHAL'S OFFICE

(STUBBS and COTTON nervously approach the door to the MARSHAL'S office.)

STUBBS: This is it then.COTTON: Is he on to us?STUBBS: Well, we'll soon find out.

(The guard outside opens the door for them.)

9: INT. SKYBASE ONE. MARSHAL'S OFFICE

(The MARSHAL sits at his desk. He watches the two men as they enter.)

MARSHAL: Ah, Stubbs and Cotton - my trusty right-hand men!

(They stand to attention...)

COTTON: Sir.STUBBS: Sir.

(...and approach his desk as the noise of the firestorms die down. The MARSHAL is looking over a globe of Solos.)

MARSHAL: Not only have you failed to capture Ky and Miss Grant, you've also let the Doctor escape to Solos.COTTON: I tried to stop him, sir. Professor Jaeger let him get out.MARSHAL:(Shouts.) Silence! Prepare to pay a last visit to Solos.STUBBS:(Puzzled.) Last visit, sir?

(The MARSHAL gets up and walks behind them.)

MARSHAL: For a while, Stubbs. And there we shall kill three birds with one stone. Mutts, Varan...and the Doctor.

(STUBBS and COTTON look at each other.)

10: EXT. SOLOS. CAVE MOUTH (NIGHT)

(The DOCTOR and VARAN have made their way to the cave mouth vacated by JO and KY. The small fire is still blazing.)

DOCTOR: Well, somebody's been here. I wonder why they left?

(VARAN hears a low growl and looks round.)

VARAN: Look!

(He points at a mutant which has appeared round a corner. The creature roars and then turns, stumbling off in fright into the darkness.)

VARAN: You saw? Such creatures are evil - diseased!DOCTOR: Perhaps...but I hope the answer to their mutation is in here.

(He taps the container and then picks up another burning branch from the fire.)

VARAN: No! No...DOCTOR: What is it? Varan, the great warrior, afraid of the dark?VARAN:(Goaded.) Varan fears nothing!DOCTOR: I'm delighted to hear it. Come on then.

(He walks past VARAN further into the cave. The warrior picks up his own torch and follows.)

11: INT. SOLOS. CAVE (NIGHT)

(KY is losing his battle against the mutants. As JO watches in fright, the creatures are growling less fearful of the brandished torch and make lunge after
lunge at a desperate KY.)

12: INT. SOLOS. CAVE PASSAGE (NIGHT)

(The DOCTOR and VARAN make their way down a narrow passage towards the sound of the fight.)

DOCTOR: This way.

13: INT. SOLOS. CAVE (NIGHT)

(KY is now surrounded by six mutants. He thrusts the torch at them again and again.)

KY: Ha!

(One mutant has climbed onto a rock above KY and attempts to attack from above. KY thrusts the torch at the creature with a cry...)

KY: Ha! Ha! Ha!

(The mutants refuse to back off.)

KY: Ha!

(KY is undaunted and continues to try and make the creatures retreat.)

KY: Ha! Ha! Ha!

(One of the mutants breaks off and makes for JO who is still sheltering in the incline. She dodges past its flailing arms as KY tries another approach.)

KY: No! Listen to me! I am Ky! You know me, my people? I come to find refuge, not to harm you!

(The appeal has no success and the mutants continue to press in. KY is driven back and he falls. In doing so, he drops the torch. The mutants converge on
him. At that moment, the DOCTOR and VARAN enter the cave. Seeing what is happening to KY, the DOCTOR puts down the container and rushes in with his torch. VARAN
watches.)

DOCTOR: Leave him alone! Go on! Back! Get back! Get back - leave him be!

(The DOCTOR'S efforts have more effect and the mutants start to retreat. VARAN draws his sword and, also with his torch, joins the DOCTOR in pushing the
mutants back.)

DOCTOR: Go on! Back! Go on! Go on!

14: INT. SOLOS. CAVE PASSAGE (NIGHT)

(Driven off by her own attacking mutant, JO has run off down a side passage and therefore not seen the arrival of the DOCTOR. She makes her way down the red
and green glowing, almost carved passage. She sees a glowing white light ahead and makes her way towards it.)

15: INT. SOLOS. RADIATION CAVE (NIGHT)

(JO enters a strange cave. Lights play all over the walls which seem to have a translucent quality. The mixtures of gold and purple tones give way to green
and yellow as JO looks round in awe. The sounds in the cave grow and grow in her head and she starts to feel disorientated. She seems to see a vague white
figure ahead of her. She puts her hands to her temples as she is overcome by the effects in the cave and slowly sinks to the floor. The white figure comes
forward. It is a being dressed in what appears to be a silver radiation suit, complete with hood with a dark visor which totally obscures its features. The
being goes up to JO...)

16: INT. SOLOS. CAVE (NIGHT)

(Having driven the mutants off, the DOCTOR and VARAN approach a nervy and wary KY.)

DOCTOR: So, you must be Ky?

(He takes off a glove and holds his hand out.)

DOCTOR: How do you do? I'm the Doctor.

(KY is puzzled but takes the DOCTOR'S hand. They shake.)

DOCTOR: That's the idea. Now then, where's Miss Grant?

(KY recovers himself.)

KY: Why are you here, Varan? Did your Overlord masters send you to hunt me?DOCTOR: Steady, old chap, he did help to save your life, you know?VARAN: The Marshal has betrayed me. The Overlords are my enemies too now, Ky.KY:(Delighted.) At last, Varan, you see the truth. Now we can work together.VARAN:(Proudly.) I need no help from you, Ky. Now I shall return to my people, and lead them in battle against the Overlords.

(KY'S face betrays his disappointment. He turns to the DOCTOR.)

KY: So, you are the Doctor - the friend of Miss Grant?DOCTOR: That's right. Now where is she?KY: I took her to a place of safety when we were attacked.DOCTOR: Good.KY: Why did you come here?DOCTOR: To find her.

(He goes over and picks up the container where he left it and holds it out to KY. VARAN watches with interest.)

DOCTOR: And to give you this.

(KY cautiously takes the container in his hands. All three watch as the top of the container rises of its own accord. KY places the container down. VARAN is
the first to reach in and take one of the contents out. It is a stone tablet as glimpsed in the experiment in the laboratory. The DOCTOR and KY help themselves
to another tablet each. They are made of some dark stone.)

VARAN:(Derisively.) Tablets! Sketchings! These are not weapons.KY: Varan is right. How can these help us in our struggle? Weapons are what we need.DOCTOR: Perhaps these tablets are worth more to you than any weapons?

(KY looks over the signs and markings carved onto the tablet.)

KY: I have seen such signs.DOCTOR: Well read it, man. Well, what does it say? Read it!KY: Well, I...I cannot. It is the language of the old ones. No one remembers. All our culture has been destroyed by the Overlords.DOCTOR: But, you...you've seen this kind of writing before?KY: Signs like these are carved in rocks all over Solos. But no one knows, no one remembers. As far as we are concerned, Doctor, they are meaningless
squiggles.DOCTOR: They must mean something, otherwise why would I have been sent here?VARAN: Then why indeed? Come. If we stay here, they will surely attack again.DOCTOR: No, I'm sorry, I can't go yet.VARAN:(Shouts.) You are fools!DOCTOR: I can't go yet - not without Miss Grant.VARAN: Is this the way to fight the Overlords? To stay here and be killed by Mutts? If you will not fight, Varan will.

(He storms off.)

DOCTOR: Now, Varan, wait.

(VARAN ignores him.)

DOCTOR:(Shouts.) Varan - wait!

(KY has put the tablets back into the container. As he picks it up, the top closes.)

KY: He will go back to his village and he and his men, for all their valour, will be wiped out. Swords are no use against the Overlord!DOCTOR:(Quietly.) No. Right, Ky - take me to Miss Grant.KY: This way, Doctor.

(KY picks up his discarded torch and lights it with the DOCTOR'S. They can hear the distant roar of a mutant. They set off.)

DOCTOR: There must be somebody on Solos who understands the old language.KY: There was a man called...er, Sondergaard - a man of learning from Earth. He came to study our culture.DOCTOR: And?KY: After a while he disappeared. Oh, it was all arranged by the Overlords.DOCTOR: Our friend, the Marshal, again, eh?

(KY smiles and nods. They continue onwards.)

17: INT. SKYBASE ONE. MARSHAL'S OFFICE

(JAEGER, STUBBS, COTTON and the MARSHAL are in the latter's office. JAEGER is sat at the desk writing while the MARSHAL and his men look over a map of the
complex structure of the caves.)

(JAEGER passes him a red pen and the MARSHAL scribbles on the map to indicate the exit points.)

MARSHAL: I want men stationed at every exit. We set off the grenades, flush 'em out - all of them - Ky, Doctor, Varan, Mutts, the lot.STUBBS: What if the grenades don't flush them out, sir?MARSHAL: Then they'll die anyway.

18: INT. SOLOS. CAVE (NIGHT)

(KY runs up to the incline where he left JO. He sees that it is deserted.)

DOCTOR: Well?KY: Well, I left her here. Perhaps she became frightened, ran off in panic.DOCTOR: Perhaps. Then we'd better start searching, hadn't we?

19: INT. SKYBASE ONE. LABORATORY

(The MARSHAL and JAEGER have gone to the laboratory. JAEGER carries a report in his hand in a red binder.)

JAEGER: I've been studying the monitoring reports since the storms.MARSHAL: I am not interested in weather reports!JAEGER: Then you should be. The reports show a sharp rise in temperature after every one of these storms.MARSHAL: So?JAEGER: There is no corresponding decrease. Marshal, Solos is getting hotter and hotter. We're moving into something which none of us have ever
experienced - the Solonian summer.MARSHAL: Mmm?JAEGER: Ever since we've been here - five hundred years - it's been spring. Now - summer. It may become too hot for any human being to live here.MARSHAL: And it may not! That's for you to find out, Jaeger. My first priority is to wipe out the Mutts.JAEGER: The reports also indicate a very sudden rise in the mutation rate. More Mutts than ever, Marshal, and all moving towards your target area.

(The MARSHAL at last shows an interest...)

MARSHAL: Good. Good then. The more the merrier.

20: EXT. SOLOS. CAVE MOUTH

(Down on Solos, it is now daylight. Four armed Skybase guards get into position outside the cave mouth. From within, VARAN watches them. One of them enters
the cave and walks past the cleft which VARAN had pressed himself into. VARAN starts to unsheathe his sword, but seeing that he has not been spotted, instead
runs out of the cave. He sprints past the three other guards who are resting outside before they can react. Nevertheless, they quickly raise their weapons and
start to fire at the escapee. They are joined by the fourth guard who runs out from inside the cave.)

21: EXT. SOLOS

(VARAN runs as fast as he can, but he is hampered by the constant explosions from the guard's guns which rip up the ground near to his feet. The four guards
give chase a short way but, the warrior having eluded them, they soon give up.)

22: INT. SOLOS. CAVE

(KY, carrying his container, returns to the main cave where he had his encounter with the mutants. He sees the DOCTOR coming from another passageway.)

KY: No?

(The DOCTOR shakes his head, a look of worry on his face.)

DOCTOR: No.KY: But she must be here!DOCTOR: Well, we'll...we'll just have to search them all over again, won't we?KY: If the torches last - and they don't attack.DOCTOR: What, you heard them?KY: They're watching us all the time.

(They hear a quiet roar from nearby.)

DOCTOR: Yes.

(The DOCTOR holds his torch up and looks at the walls. One of them, within a passage ending, has a symbol on it.)

DOCTOR: But they don't attack us in the tunnels. Only in here. This chamber must be important to them.KY: I feel it myself.DOCTOR: Feel what?KY:(Quietly.) A sensation. An awareness of being drawn here. This is a warm, like safe place - a centre. A sort of instinct.DOCTOR: Yes. Yes, it's strange. Still, let's keep searching. Come on.

(They move off. After they have gone, from a concealed entrance in the passage that the DOCTOR was looking towards, a gloved hand emerges...)

23: INT. SOLOS. CAVE PASSAGE

(The MARSHAL has joined his men on Solos. He makes his way down a passage with two guards.)

MARSHAL: Hurry up. I want those gas grenades here.

(He stops.)

MARSHAL: Give me those blast packs.

(One of the guards hesitates and the MARSHAL grabs the two packs of explosive with timers attached from him.)

MARSHAL: And no one else is to know about this - understood?

(The two guards nod and move off. A moment later STUBBS and COTTON come down the passage, each carrying a small searchlight. The MARSHAL swiftly conceals the
blast packs behind his back.)

MARSHAL: Everything ready?STUBBS: Yes sir. Er, excuse me, sir?MARSHAL: Well?STUBBS: I think we should do something about finding the Doctor, sir.MARSHAL: Do you now?STUBBS: Professor Jaeger said he was important, sir.MARSHAL: Mmm. Well Cotton?COTTON: I agree, sir.MARSHAL: I thought you would. Very well, Stubbs, you and Cotton - I'll give you fifteen minutes - no more.STUBBS: Right, sir.MARSHAL: You keep in radio contact all the way.STUBBS: Sir.MARSHAL: I wanna hear every word.

(They move further into the passage. The MARSHAL shouts after them...)

MARSHAL: And if you come across Ky, make sure you make a better job of him than you did of Varan!

(He smiles...)

24: EXT. SOLOS

(VARAN has reached hilltop. The mist is clearer here. He peers through it and descends.)

25: EXT. SOLOS. VARAN'S VILLAGE

(VARAN approaches a building in his fog-enshrouded village. A rough thatched triangular hut open at one end. VARAN calls across his village...)

VARAN:(Shouts.) ___! Varan is returned!

(He hears a moaning from within the hut and walks in. A ragged OLD MAN is crawling out of a simple bed.)

OLD MAN: Varan...VARAN: What has happened? Where are my people?OLD MAN: The fire...VARAN: Speak!OLD MAN: The firestorms...evil, a plague of evil! Fire from the sky...!

(He pulls the man to his feet.)

VARAN: Listen to me - summon my council! Go, beat the war gong!

(VARAN pushes the man towards a large circular gong which hangs on a wooden frame next to the hut. The man picks up a hammer and beats the gong. His back is
a series of insectile ridges...)

26: INT. SOLOS. CAVE PASSAGE

(STUBBS and COTTON make their way down a passage, calling as they go. They have their searchlights on.)

STUBBS: Doctor?! Doctor?COTTON: Doctor?STUBBS: Doctor?!

27: INT. SOLOS. ANOTHER CAVE PASSAGE

(Nearby, their cries reach the DOCTOR and KY.)

STUBBS:(OOV.) Doctor?! Doctor?!KY: Overlords! We must abandon the search. They will trap us here.STUBBS:(OOV.) Doctor!COTTON:(OOV.) Doctor!DOCTOR: Alright, head back to the chamber.

(They run back the way they came.)

28: INT. SOLOS. CAVE PASSAGE

STUBBS:(To COTTON.) Let's try this way.

(They move off in one direction down the passage.)

29: INT. SOLOS. CAVE

(The DOCTOR and KY re-enter the main cave. As they do so there is a faint moan. KY fails to hear it.)

KY: If they attack now...DOCTOR: Shh! Wait...listen.

(The DOCTOR looks over at a side cave. They hear another moan.)

DOCTOR: That's Jo Grant in there somewhere. (Shouts.) Jo?! Jo, are you in there? Jo...

(They move into the side cave and find JO, almost unconscious, on the ground.)

DOCTOR: Jo? Jo, are you alright?

(JO turns her head.)

DOCTOR: Jo?JO:(Faintly.) Doctor...DOCTOR: Yes, it's alright, it's me.

(There are sudden footsteps and they are illuminated in the glare of the searchlights.)

STUBBS: Ah, there you are.KY:(Shouts.) Run, Doctor!DOCTOR: No, Ky!

30: INT. SOLOS. CAVE PASSAGE

(Having forgotten to switch their radios off, their every word is relayed to a listening MARSHAL...)

KY:(OOV: Over radio.) ___.STUBBS:(OOV: Over radio.) It's us, Doctor - Stubbs and Cotton. Is Miss Grant with you?DOCTOR:(OOV: Over radio.) Yes, she's over here. She appears to be injured.

(The MARSHAL switches his baton radio off and turns to two guards next to him.)

(The guards pick up a stick grenade each and move further down the passage. They light them up and throw them down the passage. Each falls to the ground and
starts to give out a gas.)

MARSHAL: Pull out! Everyone out of the cave.

(The guards move back towards the surface. The MARSHAL attaches a blast pack to one passage wall and switches the timer on. He then attaches the second to
the other wall and extends his baton microphone.)

MARSHAL:(Into radio.) All stations: seal off exits. Fire grenades.

(He switches the second timer on and follows his retreating guards.)

31: INT. SOLOS. CAVE

(STUBBS is trying to contact the MARSHAL on his radio. The DOCTOR and KY sit down nearby.)

STUBBS:(Into radio.) Hello? Hello?

(The DOCTOR looks up at STUBBS.)

STUBBS: Lost contact.

32: INT. SOLOS. CAVE PASSAGE

(The gas in the passage grows thicker.)

33: EXT. SOLOS. VARAN'S VILLAGE

(VARAN is still alone with the OLD MAN.)

VARAN: Why does no one come? Where are my warriors?OLD MAN: Your warriors have fled, Varan.VARAN: Am I left with nothing but mutants?OLD MAN: They too. It is the way with us all, old and young, those who can walk have gone - to the mines, Varan, to the mines.VARAN: Why? Why has this curse come upon us?

(He suddenly sees the back of his right hand. A scaly, crust skin is starting to grow there. He looks at it in horror. He sinks to the ground...)

VARAN: No! No, no, no, no...!

(...but suddenly seems to hear a voice in his head as he stares into the mist...)

VARAN:(Thoughts.) Go, Varan...go to the place of sleeping...the place of darkness and light...go, Varan, go...go...go...go...

(His face clears and he struggles to his feet.)

VARAN: I was born to fight.

(Desperately trying to concentrate, he unsheathes his sword.)

VARAN: Varan...will not die sleeping!

34: INT. SOLOS. CAVE PASSAGE

(The gas is rapidly starting to fill all the passageways. The mutants within quickly succumb to its lethal effects and fall to the ground.)

35: INT. SOLOS. CAVE

(JO has recovered a great deal and is trying to remember her experiences to the others...)

JO: Passageway...full of light. Even the rocks were glowing. I remember...walking towards the light...DOCTOR: Yes?JO: And then there was this...noise in my head. I couldn't hear, I couldn't see properly. It was then I started to get dizzy.DOCTOR: Mm hm.JO: And then there was a figure...a silvery figure.DOCTOR: A mutant?JO: I don't know...DOCTOR: Well, and then what?JO: Well, then I'm...sorry, Doctor, I...fainted.DOCTOR: Ah, whatever it was, it...brought you back here.STUBBS:(To COTTON.) I'd better tell His Nibs what's going on.DOCTOR: Here, just a minute. I don't particularly want to find myself in the Marshal's hands again, thank you very much.COTTON: Better off on Skybase than in here. (To STUBBS.) You'll have to hurry, old son. The attack's due to start any minute now.DOCTOR: Attack?COTTON: Gas - the Marshal's solution to what he calls the Mutt problem.JO: Doesn't he know we're in here?KY: He knows.COTTON: I think we ought to move out now, before it's too late.

36: EXT. SOLOS

(Outside the cave, the MARSHAL speaks to SOLOS GUARD who holds a detector.)

MARSHAL: What's the count?SOLOS GUARD: It seems to be swarming with Mutts, sir. They're attracted to the place.MARSHAL: Mmm, they go there to die. They have the old idea of the elephant's graveyard. Right, should be any moment now.

(He checks his watch and looks towards the nearby cave mouth. After a second, it is ripped apart by two large explosions. The MARSHAL smiles in
satisfaction.)

37: INT. SOLOS. CAVE PASSAGE

(STUBBS is making his way back to the entrance. He stops suddenly as he smells something. Looking down a side passage, he sees the rockfall from the
explosion and a cloud of gas creeping towards him. Coughing, he runs back the way he came.)

38: INT. SOLOS. CAVE

(The DOCTOR waits in the cave with JO, KY and COTTON.)

DOCTOR: Let me see those tablets again, Ky.

(KY takes one out of the open container and passes to the DOCTOR who looks it over in frustration.)

DOCTOR: The answer must be here somewhere.

(STUBBS comes running back up to them.)

STUBBS: Doctor! Gas! They've started the attack already.COTTON: We've got to get out.STUBBS: We can't get out. The Marshal's sealed us in.COTTON: What are we going to do?